Looks like the hard top i bought recently has had some racing heritage. I found the top on eBay and bought it from Cowley Classics in Oxford. Ideal for a car that had some racing pedigree as well (possibly).
As can be seen it needs a bit of tidying up which is my summer project hopefully ready to attach to the car for next winter.
MGCC MGBCV8 races have taken place throughout the UK since the late 1980s’.
The MGCC MGBCV8 races at circuits including Silverstone, Oulton Park, Donington Park, Mallory Park, Castle Combe and Croft. Cars featured include MGB Roadsters, MGC Roadsters, MGB GT and MGB GTV8. More info at https://www.mgcc.co.uk/motorsport/racing/bcv8/
Maybe the top is on one of the cars in this video clip at https://m.youtube.com/watch?v=7_2MoFPWW8k